Coverage Plan
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September 2008 COVERAGE PLAN 1. Summary 1.1 The BBC is required under clause 35 of the Agreement to prepare a “coverage plan” detailing how it will secure the objective that, “substantially the same proportion of households in the UK as can, at the date of this Agreement, receive the analogue television services in analogue form by means of terrestrial broadcasting (that is to say, through a television aerial), can receive all the BBC’s principal television services in digital form by that means.” 1.2 This document constitutes that coverage plan. It has been prepared by the BBC and has been considered and approved by the BBC’s Executive Board and the BBC Trust. It is submitted by the BBC to the Secretary of State for approval, in line with clauses 35(3) and 35(4) of the Agreement. 1.3 The BBC estimates that analogue television is available to 98.5% of the population using a network of around 1,154 transmitting stations. This coverage plan sets out the network which is proposed to be used to provide digital terrestrial television after switchover and demonstrates that the coverage will be at least the same as, if not more than, that of analogue television. In this respect, the BBC considers that its objective is met. 1.4 The coverage plan comprises four sections: 1.4.1 the BBC’s coverage objectives and policy in relation to the digital terrestrial television platform; 1.4.2 the UHF digital transmitter plan; 1.4.3 the switchover timetable; and 1.4.4 some administrative procedures to be followed in relation to the coverage plan, including change control. 1.5 The coverage plan reflects the BBC’s current working position and state of knowledge as at September 2008. Subject to any amendments from time to time and those made by direction pursuant to clause 35(5) of the Agreement, it will become binding on the BBC from the date on which the Secretary of State grants his approval. SECTION 1: THE BBC’S COVERAGE OBJECTIVES AND POLICY FOR DIGITAL TERRESTRIAL TELEVISION 2. Coverage of analogue television 2.1 Working as part of the Government’s Digital Action Plan, the BBC has assessed the coverage of the four principal analogue television services (that is, BBC One, BBC Two, ITV1, and Channel 4) as being 98.5% of UK households. 2.2 The figure in paragraph 2.1 is based upon a complex mathematical modelling of the coverage given the known parameters of the transmitting stations in the network and the potential interference from other sources. The prediction model shared by the UK’s television spectrum planning organisations – the UK Planning Model – has been used to arrive at the assessment. It makes a number of assumptions about the equipment used by viewers to receive television services. Whilst the BBC has a high degree of confidence in the figure arrived at, it recognises that any prediction of this sort is necessarily subject to the limitations and known potential for error in the underlying model. 2.3 The BBC recognises that these assumptions may not be true in every case and that, as a result, the actual usable coverage of its analogue television services may be more or less than the estimate set out in paragraph 2.1. In particular, some viewers may not mount their receiving aerials outside their homes, or may use the aerial built into their television set, which would have the effect of reducing the usable coverage of the network. On the other hand, not all of the continental transmitters that are included in interference calculations may be on-air or operating at their fully licensed power. Viewers may also be more tolerant of interference (and low signal level) than international recommendations suggest, so a proportion of those outside the claimed coverage of the network may be watching services, albeit at a substantially reduced technical quality. These two factors would have the effect of increasing the usable coverage of the network. 2.4 The estimate set out in paragraph 2.1 is of the proportion of the population who could receive all four of the main analogue terrestrial television services using a single receiving antenna. Various factors mean that the coverage of each individual service may be slightly greater than the area covered by all four together. 2.5 The BBC therefore considers that the estimate set out in paragraph 2.1 is a fair and robust assessment of the coverage of the analogue television services based on the information available and certain common assumptions about the required technical level of service. 3. Expected coverage of the BBC’s services on digital terrestrial television 3.1 The spectrum planning for the new digital terrestrial television networks is being completed in stages, with the principal, high-power transmitting stations being planned first (as these deliver the most coverage) and the relay stations being planned to fit in around these. The plan is well advanced with the characteristics of the principal stations now defined and the majority of relay stations confirmed. 3.2 In conjunction with Digital UK and Ofcom, the Joint Frequency Planning Project has adopted a system of phased “regional lockdowns”, at which point the frequency plan for a particular ITV region is finalised and available for implementation. As at September 2008, nine of the fifteen ITV regions have been “locked down”, with a completed plan expected to be available before the end of 2008. 3.3 As a result, any estimate of coverage made before the completion of this process is liable to change. This notwithstanding, the BBC is confident that the magnitude of any such change in percentage of population covered is likely to be very small when considered across the whole of the network. 3.4 Subject to the caveat in paragraph 3.3 and the assumptions in the paragraphs following, the BBC estimates that the common coverage of the three public service multiplexes following switchover will be 98.7% of UK households. 3.5 The estimates of coverage set out in paragraph 3.4 are the result of the same mathematical model – the UK Planning Model –used to arrive at the prediction for analogue television coverage set out in paragraph 2.1. Again, some assumptions have been made concerning the performance of viewers’ receiving installations. Where these assumptions are not the same as figures set out in international recommendations, the BBC has used values which have been agreed by the Joint Frequency Planning Project and which are supported by research and the understanding of the industry in the UK. So, as far as possible, the estimates of analogue and digital coverage have been prepared on a common basis. 3.6 The BBC is satisfied that the estimates of coverage set out in paragraph 3.5 are sound and prepared on a reasonable, fair and robust basis and notes that the estimates are in excess of the figure assumed for analogue coverage and set out in paragraph 2.1. The BBC therefore considers that, if this coverage figure is realised in practice, its duty to substantially replicate the proportion of UK households served by analogue television with digital television is met by this coverage plan. 4. Coverage Policy (i) Correlation between the coverage of the analogue and digital networks 4.1 The BBC is required to substantially replicate with digital terrestrial television the proportion of UK households which can receive analogue television as at 30 June 2006, the date of the Agreement between the Secretary of State and the BBC. Through the process of converting existing analogue transmitting stations to digital working and by re-using existing frequencies at equivalent powers to the greatest extent possible, the correlation between the coverage of the two networks (that is, the degree of commonality of coverage) should be high. 4.2 At certain stations, the digital broadcasters are unable to re-use existing frequencies either because these have been identified for release for other purposes as part of the Digital Dividend Review or because they are being used for a new high-power multiplex at a neighbouring site. Where different frequencies are used, these may suffer from different levels of interference to that currently found on the analogue transmissions. Moreover, the widespread re-plan of frequencies in neighbouring countries, coupled with the additional multiplexes being accommodated in the UK plan, may cause more interference to the post-switchover transmissions even where they re-use existing frequencies. 4.3 For these reasons, the coverage of the digital network may not be fully correlated with the coverage of the analogue network. There may be a small number of areas which, although able to receive analogue television prior to switchover to an acceptable standard, cannot receive all of the public service multiplexes after switchover. The reverse is also true; some areas previously unable to receive analogue television will receive all the public service multiplexes after switchover. 4.4 With these considerations in mind, and to the extent that it is practicable to do so, the BBC will attempt – through the Joint Frequency Planning Project – to maximise the correlation between the digital coverage and analogue coverage in the preferred service area of each transmitter. (ii) Out-of-area viewing and regionality 4.5 The BBC recognises that for many different reasons viewers may make use of transmitting stations outside of their intended service area. In some instances, this is to obtain a different regional service; in others, it is because of historic reasons, such as one station being commissioned earlier than another in the original roll-out of analogue television.